Analysis of Detector Calibrations for the GHRS for Cycles 4, 5 and 6

This report presents the analysis of GHRS D1 and D2 detector calibrations encompassing Cycles 4, 5, and 6. Calibration tests examined include: dark count measurements, focus checks, flat-field count rates, sample mapping function, and line mapping function tests. Additional flat-field data from Cycles 1 to 3 were processed and displayed to demonstrate the continuing decreasing trend in the flat-field lamps response. Results of these analyses indicate the instrument has remained stable throughout the past three Cycles.